California Water Service Begins Water Infrastructure Upgrade, Continues Work To Improve Chico Water Quality, Supply
CHICO, Calif.—California Water Service (Cal Water) began a new water infrastructure upgrade in central Chico this week, and in coming weeks, will continue installing treatment to meet the U.S. Environmental Protection Agency’s 2029 deadline to comply with a new National Primary Drinking Water Regulation for certain per- and polyfluoroalkyl substances (PFAS).
“This is going to be another busy year for our team as we remain focused on improving water quality, along with supply and system reliability for our customers’ everyday and emergency needs,” said Evan Markey, District Manager of Cal Water’s Chico District. “Providing safe, clean, reliable drinking water to our customers’ homes remains our top priority.”
To help improve water supply reliability and fire protection for customers in Chico, crews will begin construction this week installing approximately 3,100 feet of new eight-inch and six-inch water main in central Chico. Work on the project, which is expected to be completed in April, will take place Monday through Friday from 7 a.m. to 5 p.m. on the following streets:
- Chestnut Street, between W. 9th and W. 12th streets
- Hazel Street, between W. 10th and W. 12th streets
- 10th St., between Chestnut Street and Hazel Street
- 11th St., between Chestnut Street and Hazel Street
To enhance water quality and comply with new PFAS regulations, later this month, Cal Water will begin installing granular-activated carbon treatment equipment and associated site piping at existing well sites, one in southern Chico and one in northern Chico. The projects are expected to be completed in May. Meanwhile, crews are continuing the work they began last month to complete the same treatment and equipment installation on two additional existing wells, also in southern and northern Chico. Construction on these wells began in December and is expected to be completed in March.
Generally, PFAS are manmade compounds that are found in a number of everyday products; these compounds are soluble in water and can travel long distances. Under the new PFAS regulation, EPA established maximum contaminant levels (MCL) of 4 parts per trillion (ppt) for both PFOA and PFOS; MCLs of 10 ppt for PFHxS, PFNA, and GenX; and a combined Hazard Index of 1.0 for PFBS, PFHxS, PFNA, and GenX. Water utilities across the country are required to monitor for these PFAS by 2027, and impacted water systems must comply with the MCLs and Hazard Index by 2029.
Cal Water regularly assesses the water quality of its existing supply sources and began monitoring all of its active water sources for these PFAS long before to the EPA ruling, Markey said. As a result, Cal Water is well-positioned to treat any water sources needed across Chico within the compliance timeframe, he added.
About California Water Service
California Water Service provides high-quality, reliable water utility services to about 109,700 people through 30,800 service connections in Chico and Hamilton City, and more than 2 million people statewide through 499,400 service connections. Cal Water’s purpose is to enhance the quality of life for customers and communities. To do so, it invests responsibly in water and wastewater infrastructure, sustainability initiatives, and community well-being. The company’s 1,200 employees live by a set of strong core values and share a commitment to protecting the planet, caring for people, and operating with the utmost integrity. The utility has been named one of “America’s Most Responsible Companies” and the “World’s Most Trustworthy Companies” by Newsweek, a USA Top Workplace, and a Great Place to Work®. More information is available at www.calwater.com. # # #
Released January 9, 2026